1. Field of the Invention
The present invention relates to a fan system including axial flow fans and ducts interposed therebetween.
2. Description of the Related Art
Japanese Patent Application Publication No. 2007-263004 (JP2007-263004A) discloses a fan system including a front axial flow fan, a rear axial flow fan, and a duct interposed between the axial flow fans. The axial flow fans each include a cylindrical housing body formed with an air channel having a suction port and a discharge port. The housing body includes four support portions that connect a motor and the housing body in the discharge port. The duct has a cylindrical duct housing. The duct housing includes eight duct blades disposed at intervals in a circumferential direction inside the duct housing and extending radially. The duct blades have the shape of a flat plate extending straight.
A conventional fan system, however, has limitations in increasing the static pressure relative to the air flow (the air flow-static pressure characteristics) and reducing fan noise.